Supplemental Cash Flow Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020	Oct. 01, 2019
Supplemental disclosure of non-cash activity:
Operating lease right-of-use assets	$ 9,795	$ 12,344
Operating lease liabilities	11,208	14,154
Increase in operating leases right-of-use assets	835	2,905	$ 3,104
Increase in operating leases liabilities	835	2,905	3,104
Supplemental disclosure of cash activity:
Interest payments	70,132	74,171	71,888
Income tax payments	4,216	3,462	546
Tax refunds received	0	1,078	315
Reconciliation of cash, cash equivalents and restricted cash:
Cash and cash equivalents	214,594	246,715	327,693
Restricted cash	37,234	27,428	14,835
Cash, Cash Equivalents, and Restricted Cash	251,828	274,143	342,528
Equity Method Investment, Nonconsolidated Investee or Group of Investees
Supplemental disclosure of non-cash activity:
Derecognition of investment in unconsolidated entities	3,641	0	0
Accounting Standards Update 2016-02
Supplemental disclosure of non-cash activity:
Operating lease right-of-use assets	0	0	13,895	$ 13,900
Operating lease liabilities	$ 0	$ 0	$ 16,028	$ 16,000